By default, the PDF working directory is found in your /wp-content/uploads/PDF_EXTENDED_TEMPLATES folder. For multisite installations we also create a subdirectory inside the PDF_EXTENDED_TEMPLATES folder using each multisite’s ID. This filter allows you to change that location (but you’ll normally want to use the gfpdf_template_location filter instead).

The multisite working directory MUST be in a publicly accessible folder (accessed via a URL) and MUST be used in conjunction with the gfpdf_multisite_template_location_uri filter. Both the gfpdf_multisite_template_location and gfpdf_multisite_template_location_uri filters should point to the same directory – one is the path and one is the URL.

Note: your web server needs write access to the folder you move the working directory to.

You can also use this filter by targeting the multisite ID directly: gfpdf_multisite_template_location_$blog_id.